The present invention relates to a printer. More particularly, the invention relates to a printer that is manually positionable on a image receiving medium for printing thereon or for detecting markings thereon.
In the state of the art, a number of printers are known that may be manually placed on an image receiving medium. The printing means of the printer or the entire printer is operable to scan over the image receiving medium in the printing operation. Thus, the medium is not fed through the printerxe2x80x94as in most office sheet printers, but the printer is placed upon the medium.
Such a printer is known from EP 564297 A. The printer disclosed in this reference has an ink jet print head which scans in two orthogonal directions over the image receiving medium, onto which the printer is manually placed. The printer is connected to a computer and capable, e.g., of printing addresses onto envelopes, but can also be used separately from the computer for printing data downloaded from the computer to the printer.
Another ink jet printer to be placed on a printing medium is disclosed in U.S. Pat. No. 5,634,730. This printer is provided with a keyboard for data inputting, but can also print images downloaded from a computer. The print head scans over the image receiving medium along a special path, e.g., helically or like a pendulum.
DE 3142937 A refers to a so-called hand stamp which is placed manually on the image receiving medium. It can print data downloaded from an accounting machine, or images consisting of user-selected fixed phrases. The hand stamp has a thermal print.
U.S. Pat. No. 5,063,451 discloses another printing apparatus which can be placed on an object and print a selected pattern by means of a scanning print head onto the surface of the object. In order to make an alignment of the printer on the printed object easier, the printer is provided with a frame member having a window through which printing is performed. Thus, the frame member is positioned such that the window is aligned in the desired printing location and then the printing mechanism is placed in its active position. Thus, the printing mechanism is movably (hinged or slidably) mounted to the frame member.
U.S. Pat. No. 4,436,439 discloses a small printer in which the image receiving medium is fed through the printer and the printed image can be viewed through a window. This printer has an ink jet print head mounted on a crank.
The printers known in the prior art are thus capable of printing an image onto an image receiving medium, and make use of a scanning print head. Printing is performed in two steps: the first one is alignment of the printer on the image receiving medium such that the image can be printed in the desired position. The second step is printing. In the prior art, alignment of the printer in the appropriate printing position is somewhat difficult, since the known direct printers do not allow viewing the image receiving medium when the printer is in position (EP 564297, U.S. Pat. No. 5,634,730, DE 3142937), or require closing of the printer after aligning (U.S. Pat. No. 5,063,451), such that the printer may accidentally slip out of the desired printing position during closing, but the user cannot notice this movement, such that printing is not always performed with perfect alignment.
The object of the present invention is hence to provide a printer of the type which is manually placed on an image receiving medium which allows an easy alignment.
According to a first aspect of the invention, there is provided a printer includes a housing arranged to be manually positioned on an image receiving medium. The housing is provided with a window, the window being arranged such that the print face is visible through the window. The printer also includes a print head provided in the housing and a print face exposed to the image receiving medium, the print face defining a region in which the print head is operable to print a desired pattern onto the image receiving medium. The printer further comprises a base station for receiving the housing when the printer is not in use, whereby the print head is protected.
The core of this aspect of the invention is thus to have a window in the housing of the printer, such that a user can see the print face and the image receiving medium.
According to another aspect of the invention, there is provided a printer including a housing arranged to be manually positioned on an image receiving medium; a print head provided in the housing; and a print face exposed to the image receiving medium. The print face defines a region in which the print head is operable to print a desired pattern onto the image receiving medium. The window is arranged such that the print face is visible through the window.
The core of this aspect of the invention is to have a window in the housing of the printer, such that a user can see the print face and the image receiving medium through the window. Since the boundaries of the print face as well as the medium are visible, it is easy for the user to move the printer over the image receiving medium until perfect alignment is obtained. Then the printing sequence can be initiated.
In a preferred embodiment of the invention, a means is provided for projecting a light spot onto the image receiving medium. Thus, alignment is made even easier for the user. These means can be a LED with a focusing lens, and/or a solid state laser. Preferably, two light spots are projected onto the image receiving medium, so that an imaginary line connecting both spots is oriented parallel to an edge of the print face.
Alternatively or additionally to the light spot, it is proposed to include a sighting arrangement within the housing of the printer, the sighting arrangement arranged such that the print face (and thus the image receiving medium) can be seen through it, and comprising two vertically separated reference features, preferably crosshairs. The user can thus look through the sighting arrangement and align the printer with the image receiving medium. Here, it is also preferred that two sighting arrangements are provided, so that an imaginary line connecting both sighting arrangements is oriented parallel to an edge of the print face.
The window can comprise a first area and a second area, the first area being clear and the second area being frosted. The first area is preferably approximately rectangular arid surrounded by the second area. Thus, the user can view through the window and the first area he or she sees corresponds to the print face, at least when viewed from a larger distance from the housing. Preferably, a window having a frosted area is provided in a printer having a sighting arrangement (e.g., crosshairs) within the housing, which can be seen through the window. In this case, alignment errors caused by parallax can be even further reduced.
The window is preferably hingedly mounted to the housing, and may comprise two parts, which are hingedly mounted together. Alternatively, the window is releasably mounted to the housing.
In another embodiment of the invention, the print face is surrounded by a thin fixed guide, the guide being sufficiently thin to allow a movement of the print head within the print face, and visible through the window. Thus, the user can easily align the guide with the image receiving medium, in another embodiment, the print face is surrounded by hingedly mounted print area guides, the print area guides being biased such that they are normally aligned vertically upstanding from a plane defined by a print face, and arranged to be moved aside by the print head (during a printing sequence), and the print area guides being visible through the window. The thin fixed guide or the hinged print area guides allow a full range of travel of the print headxe2x80x94which is normally an ink jet print head and thus has to move close to the image receiving medium, at a distance smaller than the thickness of the bottom part of the housing of the printerxe2x80x94over the print face, since they are designed to be sufficiently thin or flexible so as not to block the print head, but exactly indicate the boundaries of the print face.
According to another aspect of the invention, there is provided a printer including a housing arranged to be manually positioned on an image receiving medium; a print head provided in the housing; and a print face exposed to the image receiving medium. The print head is movable within the housing to print a desired pattern onto the image receiving medium in the region of the print face. The printer also includes a scanner operable to scan the print face and a controller connected to the scanner, the print head and a display, the display being provided within the housing of the printer or external to the printer. The controller is operable to detect markings on the image receiving medium, the markings being scanned by means of the scanner. The controller is operable to display an information referring to a direction in which the printer is to be moved in order to obtain alignment between the print face and the detected markings.
Thus, after placing the printer on an image receiving medium, the scanner first of all scans the surface of the image receiving medium adjacent the print face. This can be performed upon detection that the printer contacts the medium, or when a corresponding button has been depressed. The scanner produces image data, and the controller checks whether they include, for example, a horizontal or vertical straight line, or another special marking, such as a cross, which is defined by an intersection of two lines. The controller controls a display which indicates to the user in which direction the printer has to be moved in order to align it with the detected marking on the image receiving medium. The display may show arrows indicating the appropriate direction and/or flashing elements as LEDs to indicate in which direction to move (translate and/or rotate) the printer.
In principle, it would be possible to scan the image receiving medium repeatably after the user has moved the printer according to the displayed information, in order to check whether movement and thus alignment has been performed appropriately. Since this is somewhat time consuming, it is proposed that two spaced mouse balls are provided adjacent the print face, the mouse balls being connected to the controller and submitting an information regarding a relative movement between the printer and the image receiving medium to the controller, and the controller being operable to compare the movement measured by the mouse balls with a movement calculated by means of data obtained by the scanner and operable to display an information when the printer has been brought in a position in which the print face is aligned with the detected markings.
According to a third aspect of the invention, there is provided a combination of an image receiving medium and a printer, the printer including a housing arranged to be manually positioned on an image receiving medium; a print head provided in the housing; and a print face exposed to the image receiving medium, the print face defining a region in which the print head is operable to print a desired pattern onto the Image receiving medium. The image receiving medium is provided with pre-printed or punched alignment marks for aligning the printer to the image receiving medium.
The pre-printed or punched alignment marks make alignment of the printer on the image receiving medium easier. The image receiving medium can be a strip of labels. According to a fourth aspect of the invention, there is provided a combination of an image receiving medium and a printer, wherein the image receiving medium is an ID card, and the printer includes a housing arranged to be positioned on the ID card; a print head provided in the housing; and a print face exposed to the ID card, the print face defining a region in which the print head is operable to print a desired pattern onto the ID card. The printer prints assignment marks onto the ID card, the alignment marks being provided for alignment of the ID card in subsequent lamination.
The image receiving medium is preferably an ID card, and the alignment marks are provided for alignment of the ID card in a subsequent lamination process.
According to a fifth aspect of the invention, there is provided a combination of a base station and a printer, the printer including a housing arranged to be positioned on an image receiving medium; a print head provided in the housing; and a print face exposed to the image receiving medium, the print face defining a region in which the print head is operable to print a desired pattern onto the image receiving medium. The printer is arranged to be positioned on the base station, and the base station is provided with a stop arranged to align a print medium on the base station with respect to the printer. The position of the stop is adjustable and has a number of predetermined positions at which the stop can be arrested.
Thus, it is possible to adjust the stop according to the size of the medium to be printed. The medium is then placed upon or inserted into the base station (on which also the printer is placed, either before or after insertion of the image receiving medium), and aligned with the stop. Thus, printing can easily be performed at the desired position on the image receiving medium. Since the stop is adjustable, e.g., like a stop in a hole puncher, it can be simply adjusted to the size of the medium to be printed.